<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/welcome' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>添加商品</el-breadcrumb-item>
    </el-breadcrumb>

    <el-card>
      <!-- 消息提示区域 -->
      <el-alert
        title="添加商品信息"
        type="info"
        center
        show-icon
        :closable="false"
      >
      </el-alert>
      <!-- 步骤条区域 -->
      <el-steps
        :space="200"
        :active="activeIndex - 0"
        finish-status="success"
        align-center
      >
        <el-step title="基本信息"></el-step>
        <el-step title="商品参数"></el-step>
        <el-step title="商品属性"></el-step>
        <el-step title="商品图片"></el-step>
        <el-step title="商品内容"></el-step>
        <el-step title="完成"></el-step>
      </el-steps>

      <!-- tabs区域 -->
      <el-form
        :model="addForm"
        :rules="addFormRules"
        ref="addFormRef"
        label-width="100px"
        label-position="top"
      >
        <el-tabs
          :tab-position="'left'"
          v-model="activeIndex"
          :before-leave="beforeTabLeave"
          @tab-click="tabClicked"
        >
          <el-tab-pane label="基本信息" name="0">
            <el-form-item label="商品名称" prop="goods_name">
              <el-input v-model="addForm.goods_name"></el-input>
            </el-form-item>
            <el-form-item label="商品价格" prop="goods_price">
              <el-input v-model="addForm.goods_price" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品重量" prop="goods_weight">
              <el-input v-model="addForm.goods_weight" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品数量" prop="goods_number">
              <el-input v-model="addForm.goods_number" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品分类" prop="goods_cat">
              <el-cascader
                :options="cateList"
                :props="cascaderProps"
                v-model="addForm.goods_cat"
                clearable
                @change="handleChange"
                ref="cascaderRef"
              >
              </el-cascader>
            </el-form-item>
            <!-- 级联选择器，用来展示所有的分类 -->
          </el-tab-pane>

          <el-tab-pane label="商品参数" name="1">
            <!-- 渲染表单的Item项 -->
            <el-form-item
              v-for="item in manyTableData"
              :key="item.attr_id"
              :label="item.attr_name"
            >
              <!-- 渲染Item项的参数——采用复选框的形式 -->
              <el-checkbox-group v-model="item.attr_vals">
                <el-checkbox
                  :label="cb"
                  v-for="(cb, i) in item.attr_vals"
                  :key="i"
                  border
                ></el-checkbox>
              </el-checkbox-group>
            </el-form-item>
          </el-tab-pane>

          <el-tab-pane label="商品属性" name="2">
            <el-form-item
              v-for="item in onlyTableData"
              :key="item.attr_id"
              :label="item.attr_name"
            >
              <el-input v-model="item.attr_vals"></el-input
            ></el-form-item>
          </el-tab-pane>

          <el-tab-pane label="商品图片" name="3">
            <el-upload
              :action="uploadURL"
              :on-preview="handlePreview"
              :on-remove="handleRemove"
              list-type="picture"
              :headers="headerObj"
              :on-success="handleSuccess"
            >
              <el-button size="small" type="primary">点击上传</el-button>
              <div slot="tip" class="el-upload__tip">
                只能上传jpg/png文件，且不超过500kb
              </div>
            </el-upload>
          </el-tab-pane>

          <el-tab-pane label="商品内容" name="4">
            <!-- 富文本编辑器 -->
            <quill-editor v-model="addForm.goods_introduce"></quill-editor>
            <el-button type="primary" class="btnAdd" @click="add"
              >添加商品</el-button
            >
          </el-tab-pane>
        </el-tabs>
      </el-form>
    </el-card>

    <!-- 图片预览 -->
    <el-dialog title="图片预览" :visible.sync="previewVisible" width="50%">
      <img :src="previewPath" alt="" class="previewImg" />
    </el-dialog>
  </div>
</template>

<script>
import _ from 'lodash'

export default {
  data() {
    return {
      // 当前处于哪一个步骤
      activeIndex: '0',
      // 添加商品的表单数据对象
      addForm: {
        goods_name: '',
        goods_price: 0,
        goods_weight: 0,
        goods_number: 0,
        // 商品的分类
        goods_cat: [],
        // 上传的图片临时路径（对象）
        pics: [],
        // 介绍
        goods_introduce: '',
        // 商品的参数（数组），包含 `动态参数` 和 `静态属性`
        attrs: [],
      },
      // 添加商品的表单的验证对象
      addFormRules: {
        goods_name: [
          { required: true, message: '请输入商品名称', trigger: 'blur' },
        ],
        goods_price: [
          { required: true, message: '请输入商品价格', trigger: 'blur' },
        ],
        goods_weight: [
          { required: true, message: '请输入商品重量', trigger: 'blur' },
        ],
        goods_number: [
          { required: true, message: '请输入商品数量', trigger: 'blur' },
        ],
        goods_cat: [
          { required: true, message: '请选择商品分类', trigger: 'blur' },
        ],
      },
      // 商品分类数据列表
      cateList: [],
      // 指定级联选择器的配置对象
      cascaderProps: {
        expandTrigger: 'hover',
        checkStrictly: true,
        value: 'cat_id',
        label: 'cat_name',
        children: 'children',
      },
      // 动态参数的数据
      manyTableData: [],
      // 静态属性的数据
      onlyTableData: [],
      // 上传图片的URL地址
      uploadURL: 'http://127.0.0.1:8888/api/private/v1/upload',
      // 图片上传组件的headers请求头对象
      headerObj: {
        Authorization: window.sessionStorage.getItem('token'),
      },
      // 图片预览的请求路径
      previewPath: '',
      // 图片预览的对话框是否显示
      previewVisible: false,
    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    // 获得商品分类数据列表
    async getCateList() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status != 200) {
        return this.$message.error('获得商品分类数据列表失败')
      }
      this.cateList = res.data
    },
    // 级联选择器被选中后触发
    handleChange() {
      this.$refs.cascaderRef.dropDownVisible = false
      if (this.addForm.goods_cat.length != 3) {
        this.addForm.goods_cat = []
      }
    },
    // 在选择其他tabs页前，商品分类必须已经被选中
    beforeTabLeave(activeName, oldActiveName) {
      if (oldActiveName == 0 && this.addForm.goods_cat.length != 3) {
        this.$message.error('请先选择商品分类')
        return false
      }
    },
    // 获得商品参数
    async tabClicked() {
      let id = this.cateId
      if (this.activeIndex == 1) {
        const { data: res } = await this.$http.get(
          `categories/${id}/attributes`,
          {
            params: { sel: 'many' },
          }
        )
        if (res.meta.status != 200) {
          return this.$message.error('获取参数列表失败')
        }
        res.data.forEach((item) => {
          item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        })
        this.manyTableData = res.data
      } else if (this.activeIndex == 2) {
        const { data: res } = await this.$http.get(
          `categories/${id}/attributes`,
          {
            params: { sel: 'only' },
          }
        )
        if (res.meta.status != 200) {
          return this.$message.error('获取属性列表失败')
        }
        this.onlyTableData = res.data
      }
    },
    // 处理图片预览效果
    handlePreview(file) {
      this.previewPath = file.response.data.url
      this.previewVisible = true
    },
    // 处理移除图片的操作
    handleRemove(file) {
      const filePath = file.response.data.tmp_path
      const i = this.addForm.pics.findIndex((i) => i.pic == filePath)
      this.addForm.pics.splice(i, 1)
    },
    // 上传图片成功时，将图片临时路径保存起来
    handleSuccess(response) {
      this.addForm.pics.push({ pic: response.data.tmp_path })
    },
    // 添加商品
    add() {
      this.$refs.addFormRef.validate(async (valid) => {
        if (!valid) {
          this.$message.error('请填写必要的表单项')
        }
        this.manyTableData.forEach((item) => {
          let newInfo = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals.join(' '),
          }
          this.addForm.attrs.push(newInfo)
        })
        this.onlyTableData.forEach((item) => {
          let newInfo = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals,
          }
          this.addForm.attrs.push(newInfo)
        })
        // 采用深拷贝是因为级联选择器里绑定的addForm.goods_cat要求是数组，而发送请求时需要是字符串，如果不额外复制一份，则会产生冲突
        let form = _.cloneDeep(this.addForm)
        form.goods_cat = form.goods_cat.join(',')
        const { data: res } = await this.$http.post('goods', form)
        if (res.meta.status != 201) {
          this.$message.error('添加商品失败')
        }
        this.$message.success('添加商品成功')
        this.$router.push('/goods')
      })
    },
  },
  computed: {
    // 当前选中的三级分类的id
    cateId() {
      if (this.addForm.goods_cat.length == 3) {
        return this.addForm.goods_cat[2]
      }
      return ''
    },
  },
}
</script>

<style lang="less" scoped>
.el-checkbox {
  margin: 0 10px 0 0 !important;
}

.previewImg {
  width: 100%;
}

.btnAdd {
  margin-top: 15px;
}
</style>